To make the dough, boil the potatoes in salt water (with skin on!) until cooked, but not mealy and mushy.
Drain well in colander for about 10 minutes.
While they are still warm, peel, then mash thoroughly.
Stir in the flour and season to taste with a little salt.
The dough is now ready.

While the potatoes are boiling, make the filling.
Melt butter with olive oil over medium to high heat.
Add the onions and soften until it is translucent and lightly browned.
Now add all the spices and cook for another minute.
Add the ground beef, stirring and breaking it up.
Stop stirring and let it stick for a minute or so. That way it can stick to the pan and brown a little, which adds more flavor to the meat.
Cook for about 5-8 minutes, until the meat is nicely browned.
Finally stir in pine nuts, tomato purée and parsley.
Season with salt and pepper.

Now to prepare the potato cakes.
Make sure your hands are dry.
Then flour them, as well as the working surface.
Divide the dough into four balls.
Flatten one ball to a disc of about 1cm thickness.
Place two tablespoons of filling in the center, then bring up the sides of the dough-disc, in order to enclose the meat filling.
Neaten the shape and patch up any cracks and gaps.
The result should look like a round patty, 10cm across and about 3-4cm thick.
Repeat with the other dough balls, always making sure that wherever you place the dough/patties the working surface is well-floured, to prevent the dough from sticking.

Generously cover the bottom of a frying pan with oil, about 3-4mm deep.
Place over medium to high heat, until hot and nearly smoking.
Gently lift up the cakes with a spatula and carefully lower into the oil, one by one.
Do not disturb until they are a dark golden color and crispy on the bottom, then carefully turn the cakes with the spatula, in order to brown the other side, as well.

When done, take out and using kitchen paper gently dab off any excess oil.
Keep warm in a low oven, or serve immediately.

We served our potato cakes with:

200 g Greek yoghurt, thinned with 2tbsp of milk and seasoned with one garlic clove crushed to a paste with salt using mortar and pestle.

Notes

For the party I will try to turn the cakes more into bite-sized balls...We'll see how that goes.

You have to be quite careful not to make the potato dough tear apart.

Also, make sure the potatoes don't cook too long.
If they get too mushy the dough will be much more difficult to handle.